Glass substrates have been replaced with substrates for flexible displays as materials of substrates for display apparatuses. The matrices with glass fibers or woven glass fibers impregnated may be used as substrates for flexible displays. Since the matrices of silicone materials have high thermal expansion coefficient over glass fibers, the substrates will be crack or break when treating flexible substrates at a high temperature. In addition, since there are problems of an occurrence of surface roughness and a difference of modulus of barrier layers and substrates when laminating barrier layers on substrates because the matrices comprise glass fibers, it is not possible to laminate barrier layers on substrates with high adhesion. Thus, researches on the technologies for forming buffer layers between barrier layers and substrates have been studied.